How to - Wildlife

Save the bees: How to attract pollinators to your yard

It sounds like something out of a science fiction movie—or nightmare: millions of honeybees suddenly dying off, their bodies never found. Scientists have named the phenomenon “Colony Collapse Disorder,” but they aren’t united on the reason. Theories abound as to the cause of the mass die-off, ranging from the unlikely (cellphones affecting bees’ navigational abilities) to the more plausible though still debated (widespread pesticide use).

Recently, researchers identified a virus (Israeli acute paralysis virus) present in CCD-infected bees, though a causal link has not been verified. Estimates vary, but CCD has resulted in losses of 30 per cent of managed honeybee colonies in the U.S., with unexplained losses being reported in Canada over several years.

Much of the recent focus has been on the state of honeybees (of the genus Apis), a non-native species of crucial importance for the pollination of agricultural crops—everything from apples to onions. Colonies of honeybees are trucked across the U.S. and between Canadian provinces to pollinate flowers and ensure fruit and seed set in commercial crops. The economic value of bees’ pollination services is estimated at $14 billion annually in the U.S. alone; approximately one-third of the continent’s food supply comes from plants that require insect pollinators.

Overshadowed by the press coverage of honeybees, however, is the decline of important pollinators such as native bees in Canada. “We’re losing species of wild bees,” alerts Peter Kevan, a professor at Ontario’s University of Guelph, and an entomology and botany expert. “Two native bumblebee species that used to be the most common bees in Ontario and one species out West all seem to be in massive decline, and may be extinct in some of their habitats already.”

Sheila Colla, a doctoral candidate at York University in Toronto, has been studying populations of native bumblebees (Bombus spp.) in Eastern Canada, and her research confirms significant losses. “Several bee species in southern Ontario show evidence of decline over the past 30 years,” says Colla. Her findings echo those of a 2006 U.S. report by the National Academy of Sciences called Status of Pollinators in North America, which concluded that “Long-term population trends for several wild bee species (notably bumblebees) and some butterflies, bats and hummingbirds are demonstrably downward.” In fact, as far back as 1995, pollinators—there are more than 1,000 species of pollinating insects in Canada including bees, wasps, flies, beetles, moths, butterflies—around the world have been under a great deal of stress, as documented in Stephen Buchmann and Gary Nabhan’s book, The Forgotten Pollinators. Many flowering plants depend on insects to transfer pollen grains from male to female flower parts, where the pollen fertilizes the egg, and produces fruit. Colony Collapse Disorder may have put honeybees in the headlines, but it’s only the tip of the proverbial iceberg.